[Identification of mutation for drug resistance gene in cutaneous leishmaniasis]

Cutaneous leishmaniasis is a common parasitic disease and one of the health problems world wide. The pentavalent antimonial drugs [e.g. pentostam and Glucantime] are the first line treatment for leishmaniasis, and resistance to these drugs is a serious problem. Using PCR method, this study was carried out to identify the mutation for sodium stibogluconate resistance gene in cutaneous leishmaniasis cases referred to different health centers during 2006-8. This descriptive study was conducted on 150 isolates of leishmania major and leishmania tropica to identify the mutation in drug resistance gene. Promastigote clones were cultured in enriched RPMI 1640 medium and then the genomic DNA was isolated and using a pair of primers, a 400 bp of the gene was amplified. Finally, the PCR products were screened by conformation sensitive gel electrophoresis [CSGE] method and then the mutation was confirmed using RFLP with Sdu1 enzyme. Screening using CSGE and RFLP methods showed that 6.3% of the samples carried a mutation for drug resistance gene. Results showed a resistance for cutaneous leishmania against sodium stibogluconate. Further studies are required to determine the biochemical mechanism of this resistance

[Isolation and molecular identification of Acanthamoeba in surface stagnant waters of Qazvin]

Background: Regarding the increasing number of acanthamoebiasis cases in recent decades, investigating the environmental pollution of this amoeba is now a focus of more attention. Surface stagnant water is considered as one of the important sources of human infections

Objective: The aim of this study was isolation and molecular identification of Acanthamoeba spp in surface stagnant waters of Qazvin

Methods: This was a descriptive study carried out in the autumn of 2010. A total of 40 samples of surface stagnant waters from the city parks and squares in Qazvin were collected. Samples were initially filtered using 0.45 micro nitrocellulose membrane filters and later the residual components left on filter membrane cultured on non-nutrient agar. The cultures media were microscopically examined for the presence of trophozoites and cysts of free-living amoebae. Positive cultures for amoebae were examined by PCR [polymerase chain reaction] method using specific primers for the genus of Acanthamoeba

Findings: Free-living amoebae were identified in 32 [80%] samples by culture method. In addition, Acanthamoeba was identified by PCR method in 14 [43.8%] cases of positive cultures showing a nearly 500bp band

Conclusion: considering the prevalent of Acanthamoeba in surface stagnant waters of Qazvin, more attention to the potential role of such waters in transmission of infection by the regional clinicians and health practitioners is necessary

Molecular epidemiology of human intestinal amoebas in Iran

Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran

[Detection of drug resistance gene in trichomonas vaginalis by PCR]

Trichomoniasis is a worldwide protozoan parasitic disease. Considering the importance of the disease in public health and the controversial ideas about the prevalence of drug resistance, this study was designed to determine the prevalence of metronidazole resistance gene in trichomonas vaginalis [T. vaginalis] with PCR-RFLP method in Tehran and in Kashan. In this descriptive study 140 samples of T. vaginalis in patients with T. vaginalis infections were collected and assessed microscopically. Then they were isolated and examined by culturing in dorset's medium, DNA extraction and PCR amplification. The PCR products were analyzed using RFLP and suspected samples were sequenced. All but 7 samples were T. vaginalis positive by PCR. Sixty-two samples [44.4%] were examined by microscopic, culture and PCR techniques; 12 samples [8.5%] by microscope and PCR, 56 samples [40%] by culture and PCR and other 3 samples [2.1%] were positive only by PCR. Two samples [1.5%] were also examined for detection of mutation in 18S rRNA gene with RFLP in Tehran. This study shows that T. vaginalis infections in the female population living in Tehran are metronidazole-resistant. Since metronidazole is considered as the drug choice for T. vaginalis infections, more studies are recommended for identification of the drug resistance mechanisms and prevention of the disease

[Evaluation of parasitic and fungal contamination and physicochemical parameters of indoor public swimming pools in Kashan during 2008-9]

Swimming in indoor public pools may lead to transmission of contagious diseases such as ear problems, foot tinea, conjunctivitis and amoebic meningoencephalitis in swimmers. The aim of this study was to determine the types of fungal and parasitic contamination and physicochemical parameters of indoor public swimming pools in Kashan. In this cross-sectional study, 200 water samples were collected from surface and depth of four swimming pools of Kashan during 2008-9. Physicochemical parameters such as, temperature, pH, residual chlorine and turbidity of the pools were studied. Samples were tested for the presence of parasitic and fungal contamination by specific mediums. The residual chlorine in 71% of samples was standard. The average pH level was 7.7 and 88% of samples were standard. No parasite and free living amoebae were observed. The prevalence of saprophytic and opportunistic fungi was 42% in surface and 12% in depth, which was not significant in different swimming pools [P=0.95]. Twelve species of saprophytic and opportunistic fungi were isolated; the highest and the lowest number of species were aspergillus [50%] and fusarium [3.7%], respectively. The residual chlorine in fungal contamination between swimming pools was less than standard [P=0.014]. Although no parasites and free living amoebae were observed in Kashan's swimming pools, the prevalence of saprophytic and opportunistic fungi was relatively high. Such condition may be attributed to low concentration of residual chlorine, inadequate water treatment and water high temperature

Application of flat plate solar collector for thermal disinfection of wastewater effluents

Application of solar energy for wastewater treatment has shown to have the least negative effects and costs. This experimental research was carried out in pilot-scale on the effluent of the extended aeration activated sludge wastewater treatment system in Kashan. The plant is located at the Kashan University of Medical Sciences campus and receives about 100 m[3]/d sewage from official and residential building blocks. In this study thermal disinfection of the effluent in 55 Degree C for 2 hours using flat plat solar collector [FPSC] was investigated. During the study in the beginning of every week, one day was selected randomly and the pilot was run. The pilot influent temperature was the same as ambient air throughout the day. If the liquid temperature within the pilot increased above 55 Degree C, a thermostatic valve opened. Passed liquid was maintained for 2 hours in this temperature. Whenever the volume of disinfected effluent was measurable fecal MPN test and Nemathoda eggs count-up were done according to the Standard Methods and Leeds-II directions, respectively. In 200 days from April to November the geometric mean of fecal coliform never exceeded the WHO guideline [1000 MPN/100mL], but in 5 days [21%] it exceeded the Iranian standard [400/100mL]. Mathematical mean of Nemathoda eggs was less than 1 per liter [Engelberg Index] persistently. The mean of hydraulic loading rates was calculated 83.25 L/d m[2] while it decreased to 41.85L/d.m[2] in the days without thermal reclamation

Detection of drug resistance gene in cutaneous leishmaniasis by PCR in some endemic areas of Iran

Cutaneous leishmaniasis is still a health problem in many rural and urban regions of Iran and drug resistance has emerged as a major impediment in the treatment of leishmaniasis. This study aims to determine the drug resistance gene in cutaneous leishmaniasis by PCR in some endemic areas of Iran. Ninety seven samples were collected from ulcers of leishmaniasis patients from some endemic areas of Iran. The Giemsa stained samples were examined microscopically and cultured in NNN and RPMI 1640 mediums for parasite detection. After DNA extraction, PCR was done by a pair of specific primers. For detection of mutation in DNA, first PCR products were electrophoresed on CSGE gel. The suspected samples were compared by sequencing and RFLP results were demonstrated. Comparison of DNA derived from a wild type cell and mutant cell was undertaken by CSGE and sequencing methods. Among 90 isolates [92.8%] examined for detection of mutation in gene with CSGE and RFLP, 10 [11.1%] revealed a disorder in sequencing selection for unresponsive to drug. Drug resistance in cutaneous leishmaniasis to sodium stiboglocanat is probably due to a mutation in a genome. A field study is needed to determine the distribution of drug resistance and other gene mutations involved in unresponsiveness to drugs in leishmaniasis endemic areas of Iran

overview of Toxocara cati infection in stray cats in the metropolitan region of Tehran, Iran, and a comparison of two diagnostic methods

Toxocara cati is one of the most important and widespread of the helminth zoonosis. In the present study, helminthosis due to Toxocara cati in 55 stray cats in Tehran was studied by necropsy. In addition, two different diagnostic methods, including serological and coprological tests, for infection with this parasite were compared. The dot-ELISA assay used Toxocaracati crude antigens to evaluate the presence of serum antibodies against the mature nematode. The coprological sedimentation method was carried out to assess the output of eggs. In autopsied cats, 52.7% were infected with T. cati. Seropositive cases were detected in 53.8% of examined cats, whereas the prevalence in feces was 40%. The sensitivity and specificity for dot-ELISA method was 65.5% and 60.9% respectively. In sedimentation method the sensitivity was 69%, and the specificity was 92.3%. The positive and negative predictive values for dot-ELISA and sedimentation were 67.9%, 58.3% and 90.9%, 72.2% respectively. These results suggest that coprological methods for diagnostic and control programs of toxocariosis in cats are the optimal investigations

Study on ITS1 gene of Iranian Trichomonas vaginalis by molecular methods

Trichomoniasis is a worldwide protozoan parasitic disease and metronidazole is a choice drug for its treatment. Because of disease importance in public health and its controversial ideas about the prevalence of drug resistance, this study was carried out. Fifty-two suspected vaginal samples were collected from 2006 to 2007 in Gynecology Maryam Hospital, Tehran, Iran. All isolates were examined by microscopic, culture and PCR techniques. The PCR products were analyzed by RFLP and CSGE methods and two suspected samples were sequenced. Trichomonas vaginalis was identified from all 52 samples. Of 52 isolates, 45 samples were successfully cultured and amplified by PCR except one. Seven were positive only by PCR. Finally, ITS1 fragment was successfully amplified in 51 of 52. CSGE analysis and PCR products digestion by MspI followed by sequencing showed nucleotide mutation at position 209 [C209T] of the ITS1 fragment in two [3.9% of them. The results showed mutation in ITS1 fragment of T. vaginalis in two [3.9%] of Iranian isolates which may be related to metronidazole resistance

Evaluation of a single PCR assays on Cp5 gene for differentiation of Entamoeba histolytica and E.dispar

We examined a molecular method with a single-PCR for amplification of a part of CP5 gene enabling us to differentiate the pathogenic species, Entamoeba histolytica, from the non-pathogenic species, E. dispar. We developed a single PCR method for this purpose. After investigation of GenBank, primer pairs were designed from highly conserved regions of cysteine proteinase [CP5] gene. The primers were utilized in PCR using isolated genomic DNA template of E. histolytica and the PCR products were then sequenced. The same primer and method for PCR was used for isolated genomic DNA template of E. dispar. A fragment of about 950 bp was isolated in PCR by using DNA from E. histolytica, however, no banding pattern was produced by using the same primers for E. dispar. We characterized CP5 gene at molecular level in E. histolytica isolates from 22 positive; including 20 non-dysentery samples isolated from both cities as well as two dysentery samples isolated only from Tabriz. Nucleotide sequence comparison in gene data banks [NCBI, NIH] revealed significant homology with CP5 gene in E. histolytica isolates. We developed a PCR method, which could detect simply and rapidly E. histolytica by amplifying a specific PCR fragment

[Differential diagnosis of Entamoeba histolytica from Entamoeba dispar and study on the intestinal parasites in rural areas of Ahwaz and Hamidieh]

Differential diagnosis of Entamoeba histolytica and Entamoeba dispar is important in clinical and epidemiological studies. The two organisms are morphologically identical but they differ in their genetics, biochemistry, and pathogenicity. The present study was carried out with the aim of distinguishing the two species and determining the prevalence of each organism in the rural areas of Ahwaz and Hamidieh. A total of 782 stool specimens were randomly collected and examined by formalin-ether concentration and direct methods. Twenty-one isolates of E. histolytica/ E. dispar were successfully cultured on Robinson's medium. DNA was extracted by the phenol/chloroform method and identified by PCR-RFLP after digestion with HinfI. Over 75% of the individuals were infected with at least one of the intestinal parasites. Entamoeba coli infection rates were very high [51.9%] among the population, while only 0.76% of individuals were positive for Dientamoeba fragilis. Sixty-five individual [8/3%] were infected with E. histolytica /E. dispar. The PCR-RFLP showed that 19 samples [90.48%] were positive for E. dispar; one sample [4.76%] was positive for E. histolytica and another sample [4.76%] showed mixed infection. Conclusion These findings show that the nonpathogenic E. dispar is predominant in Ahwaz and Hamidieh rural area

Survey of echinococcosis and hydatidosis in Kashan region, Central Iran

Hydatidosis is one of the major zoonotic diseases that cause considerable economic losses and public health problems worldwide. The present study was conducted to determine the prevalence of E. granulosus in domestic and wild carnivores and the infection rate of hydatid cyst in slaughtered animals and people in Kashan area, central Iran. A total of 142 carnivores including 70 stray dogs, 40 jackals, 22 red foxes, and 10 wolves were examined for the presence of E. granulosus, as well as, 170510 slaughtered sheep, 162665 goats and 13059 cattle for hydatid cyst infection. In addition, 500 inhabitants in rural areas were examined for antibodies to hydatid cyst. Results indicated that 43.7% of carnivores were infected with E. granulosus. Infection rate in slaughtered animals was 2.7%. Overall, the seroprevalence rate in human cases was 2.4%. Eighty-five patients including 47 females and 38 males were hospitalized. The mean annual incidence rate of hydatidosis in human was three cases per 100 000 populations. In general, the situation of the hydatidosis in the livestock and human and echinococcosis in the carnivores of the Kashan is similar to the other zones in Iran

field study of the distribution of entamoeba histolytica / dispar cyst passers in northern, central, and southern Iran

Amoebiasis is one of the most important human diseases in many countries especially in tropical and sub-tropical regions. This study was carried out from August 1999 to February 2002 in order to determine the ratio of Entamoeba histolytica / Entamoeba dispar in some regions of Iran. A total of 16, 592 stool samples were randomly collected from different agegroups in central, northern and southern Iran both from urban and rural areas. The samples were examined by direct and formalin-ether concentration methods. Two hundred and twenty six samples [1.36%] were positive for E. histolytica/E. dispar cyst [C.I = 1.18-1.54%]. The prevalence of infection with E. histolytica/E. dispar was 0.78%, 3.9% and 4.6% for central, northern and southern part of Iran, respectively. The minimum rate of prevalence was 0.6% in Tehran, Yazd and Ardekan [central Iran], while the highest rate [8.3%] was seen in rural areas of Ahwaz [southern Iran].The study showed that ratio of E. histolytica /E. dispar was higher in southern regions [tropical and subtropical] than other regions. It seems that more sanitary facilities and health trainings are needed in different parts of the country, especially in southern Iran, where the rate of infection is high